*: Fix multi-account crashes and avatar accessibility
- Replace .first {} with .firstOrNull {} in feeds() and
subscribedLabelers() to handle accounts without SavedFeedsPrefV2
or LabelersPref preferences
- Replace \!\! with safe returns in notification post lookups for
deleted/unavailable posts
- Avatar always renders and is long-pressable even when user profile
hasn't loaded yet
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>